In this article I discuss the initiatives developed by transgender people in order to ensure the application of the Gender Identity Law (Law 26. 743) in healthcare institutions. Based on the concepts of bio-citizenship and biological citizenship, I analyze the demands elaborated by the transgender population in Argentina. The corpus is formed of press articles and in-depth interviews with referents of trans organizations. I affirm that the approval of the Gender Identity Law reconfigured dialogues and tensions between health professionals and transgender people, within the framework of a global transformation in the role of patients and medical authority critiques.